The invention relates to a camshaft adjuster for an internal combustion engine, in which lubrication is performed by a lubricant flow.
Camshaft adjusters can be roughly classified as follows:
A. Phase adjusters with a control element, that is, a functional unit, which joins in the mass flow or energy flow formed, for example, hydraulically, electrically, or mechanically and rotates with gear elements of the camshaft adjuster.
B. Phase adjusters with a separate setting element, that is, a functional unit, in which the control parameter required for the control method of the control element is formed from the controller output parameter, and a separate control element. Here, there are the following structural forms:
a. Phase adjusters with a co-rotating actuator and a co-rotating control element, for example, a step-up ratio gear, whose adjustment shaft can be advanced by a co-rotating hydraulic motor or centrifugal force motor and can be reset by a spring.
b. Phase adjusters with a co-rotating control element and a stationary, engine-fixed actuator, for example, an electric motor or an electrical or mechanical brake, see also DE 100 38 354 A1, DE 102 05 034 A1, EP 1 043 482 B1.
c. Phase adjusters with a direction-dependent combination of solutions according to a. and b., for example, an engine-fixed brake, in which part of the brake power is used for adjustments toward an advanced position, in order to tension a spring, which allows resetting after the brake is deactivated, see also DE 102 24 446 A1, WO 03-098010, US 2003 0226534, DE 103 17 607 A1.
In systems according to B.a. to B.c., actuators and control elements are connected to each other by an adjustment shaft. The connection can be switchable or non-switchable, detachable or non-detachable, lash-free or with lash, and flexible or stiff. Independent of the structural form, the adjustment energy can be realized in the form of supply through a drive output and/or brake output, as well as with the use of leakage power of the shaft system (e.g., friction) and/or inertia and/or centrifugal force. Braking, advantageously in the adjustment direction of “retarded” can also be realized under the full use or shared use of the friction power of the camshaft. A camshaft adjuster can be equipped with or without mechanical limiting of the adjustment range. As a gear in a camshaft adjuster, one-stage or multiple-stage triple-shaft gears and/or multiple links or coupling gears are used, for example, in structural form as a wobble-plate gear, eccentric gear, planetary gear, undulating gear, cam-plate gear, multiple-link or linked gear, or combinations of the individual structural forms in a multiple-stage construction.
For operation of the camshaft adjuster, a lubricant must be fed to lubricating positions, especially bearing positions and/or rolling toothed sections, wherein the lubricant is used for lubricating and/or cooling components of the camshaft adjuster that can move relative to each other. For this purpose, the camshaft adjuster has a lubricant circuit, which can be coupled, for example, with the lubricant circuit of the internal combustion engine.
From DE 102 48 355 A1, it is known to feed lubricant to a camshaft via a camshaft bearing. For this purpose, the cylinder head or the camshaft bearing has a supply channel oriented in the radial direction to the camshaft. A receiving channel (here also oriented in the radial direction) is arranged aligned with the supply channel in the camshaft and moves relative to the supply channel. In the region of the receiving channel, the camshaft has a peripheral groove in the circumferential direction, which guarantees that the transfer of lubricant from the supply channel to the receiving channel is continuous and is possible for every angle position of the camshaft, wherein the lubricant is led from the supply channel via the groove to the receiving channel.